Bridge



- Patented Jan. 17,1882.

J. B. MOPHERSON.

BRIDGE.

(No Model) WITNESSES 'UNITED STAT-Es PATENT OFFICE,

'BRIDGE.

SPECIFICATION forming part of Letters Patent No. 252,487, dated JanuaryI7, 1882. Application filed June 28, 1881. (No model.)

To all whom it may concern:

Be it known that I, JOHN B. MoPHERsoN, of Bunker Hill, in the county ofMacoupin and State of Illinois, have-invented certain new and usefulImprovements in Bridges; and I do here'uy declare that the following isa full, clear, and exact description of the invention, which will enableothers skilled in the art to which it appertains to make and use thesame, reference hein g had to the accompanying d rawings, which form apart of this specification, and in which- Figure l is aside elevation ofmy improved bridge. Fig. 2 is a bottom plan of the same. Fig.3 is alongitudinal vertical section through one of the chords and braces, andFig. 4 is a cross-section through one of the bolsters with itsclamping-rods and clamp.

Similar letters of reference indicate corresponding parts in all thefigures.

My invention relates to bridges made of wood, or chiefly of wood,calculated to have a span of from forty to seventy feet, more or less;and it consists in theimprovements hereinafter set forth, andparticularly pointed out in the claims.

In the annexed drawings, A A are the bedtimbers, which rest upon thepier-posts.

B B are bolsters, made preferably of castjron, of the shape shown in thedrawings, from which it will be seen that each bolster consists of a;bottom plate or body, a, made with two laterally-projecting ears, b b,which are bored through vertically and countersunk on their under sidefor the insertion of the headed clamping-rods C. At its outer end platea is cast with a rounded shoulder, c. The plate or base a is boredthrough, longitudinally, as shown at d, Fig. 3, for the insertion andattachment of the ends of the wire rope or chord D, the heads 6 of whichare embedded in countersunk recesses d.

E is the sleeper or string-piece, of which there may be one or morepassing from end to end, restingupon and bolted to the bed-tim- -bersAA. I

F isthe central cross-joist, and G G the firmly against the strut.

K is the tension-rod, the upper end of which is inserted through andnutted to a cap-plate, is, placed over the joint of the struts H H,while its lower end is inserted through and nutted to the under side ofthe projecting ends of the crossjoist F, on the out-side of the chord D.

This bridge, while being simple and inexpensive in its construction, iscapable of standing a heavy strain, and can be made in single spans offrom forty to seventy feet, and even more, without additional braces orother strengthening devices.

am aware that it is old to employ, in connection with the bolsters, thebed-pieces, and the inclined timbers, obliquely-arranged yoke or stapleshaped bolts; to employ bolsters with j the inclined pieces or archesseated therein and having the stringers or rods passing through them; toemploy underneath shouldered bolsters in connection with side pieces,rods, and bolts, securing them together; to employ rightangled bolsterswith the inclined pieces or timbers and rods bolted to the bolsters, andbolts extending from the ends of said bolsters upon the sides of theinclined pieces, and to employ bolsters adapted to permit the chords orrods to pass through and be bolted to them'and form shoulders for thelower ends of the inclined pieces to rest against, with bolts passingthrough them and the inclined pieces.

I Having thus described my invention, I claim auddesire to secure byLetters Patent of the United States- 1. The combination, in a bridge ofthe described class, of the end or bed timbers, A A, shouldered bolstersB, having perforated ears I) b and longitudinal countersunk bore 01 d,headed chords D, made of wire rope, struts or braces H, beveledclamping-plates I, and nut In testimony that I elziiin the foregoing as[O ted tie-bolts C 0, all constructed and combined my own I havehereunto affixed my signature substantially as and for the purposeherein in presence of two witnesses. shown and set forth.

2. The bolster B; composed of a longitudi- JOHN B. MCPHERSON.many-perforated base-plate, a, having shoulder c andlaterally-projecting perforated ears I) b, Witnesses:

as and for the purpose herein shown and speei- T. G. WO0D, tied. I .WM,PETEFISH.

